There is no way that it should be getting less than 25 shots if it is chrono'd at 280.
I'd suspect the valve to be kept open by a weak valve spring if there is absolutely no leaks. I wouldn't rule out a leak as they can be very small.
Most of the time I have a leak it's from not screwing the co2 cap in enough.
Once you get it working.... It's possibly the most fun gun I've ever had.
Originally Posted by HurtCow
That's interesting... it's got a cat for a recoil pad. Must shoulder kinda awkwardly.